Debt	6 Months Ended
Feb. 29, 2016
Debt Disclosure [Abstract]
Short-Term Borrowings	On April 6, 2016, the Company and certain of its subsidiaries entered into the Third Amended and Restated Credit Agreement (the "Amended Credit Agreement") with Bank of America, N.A. as administrative agent, and the other lenders party thereto, which amends and restates the Company’s existing unsecured credit agreement. The Amended Credit Agreement provides for $335 million and C$15 million in senior secured revolving credit facilities maturing in April 2021. Subject to the terms and conditions of the Amended Credit Agreement, the Company may request that the commitments under the U.S. credit facility be increased by an aggregate amount not exceeding $100 million. Prior to its amendment and renewal, the credit agreement provided for revolving loans of $670 million and C$30 million maturing in April 2017. The Company had $198 million in borrowings outstanding under the credit agreement as of April 5, 2016 prior to its amendment and renewal. As of February 29, 2016 and August 31, 2015, borrowings outstanding under the credit agreement were $185 million and $215 million, respectively. Interest rates on outstanding indebtedness under the Amended Credit Agreement are based, at the Company’s option, on either the London Interbank Offered Rate ("LIBOR"), or the Canadian equivalent, plus a spread of between 1.75% and 2.75%, with the amount of the spread based on a pricing grid tied to the Company’s leverage ratio but no less than 2.50% for the fiscal quarters ending May 31, 2016, August 31, 2016 and November 30, 2016, or the greater of the prime rate, the federal funds rate plus 0.50% or the daily rate equal to one-month LIBOR plus 1.75%, in each case plus a spread of between 0.00% and 1.00% based on a pricing grid tied to the Company's leverage ratio. In addition, commitment fees are payable on the unused portion of the credit facilities at rates between 0.20% and 0.40% based on a pricing grid tied to the Company’s leverage ratio. The Amended Credit Agreement contains certain customary covenants, including covenants that limit the ability of the Company and its subsidiaries to enter into certain types of transactions. Financial covenants include covenants requiring maintenance of a minimum fixed charge coverage ratio, a maximum leverage ratio and a minimum asset coverage ratio. The Company’s obligations under the Amended Credit Agreement are guaranteed by substantially all of its subsidiaries. The credit facilities and the related guarantees are secured by senior first priority liens on certain of the Company's and its subsidiaries’ assets, including equipment, inventory and accounts receivable. The Company also had an unsecured, uncommitted $25 million credit line with Wells Fargo Bank, N.A. that expired on April 1, 2016. Interest rates were set by the bank at the time of borrowing. The Company had no borrowings outstanding under this credit line as of February 29, 2016 and August 31, 2015.

On April 6, 2016, the Company and certain of its subsidiaries entered into the Third Amended and Restated Credit Agreement (the "Amended Credit Agreement") with Bank of America, N.A. as administrative agent, and the other lenders party thereto, which amends and restates the Company’s existing unsecured credit agreement. The Amended Credit Agreement provides for $335 million and C$15 million in senior secured revolving credit facilities maturing in April 2021. Subject to the terms and conditions of the Amended Credit Agreement, the Company may request that the commitments under the U.S. credit facility be increased by an aggregate amount not exceeding $100 million. Prior to its amendment and renewal, the credit agreement provided for revolving loans of $670 million and C$30 million maturing in April 2017. The Company had $198 million in borrowings outstanding under the credit agreement as of April 5, 2016 prior to its amendment and renewal. As of February 29, 2016 and August 31, 2015, borrowings outstanding under the credit agreement were $185 million and $215 million, respectively.

Interest rates on outstanding indebtedness under the Amended Credit Agreement are based, at the Company’s option, on either the London Interbank Offered Rate ("LIBOR"), or the Canadian equivalent, plus a spread of between 1.75% and 2.75%, with the amount of the spread based on a pricing grid tied to the Company’s leverage ratio but no less than 2.50% for the fiscal quarters ending May 31, 2016, August 31, 2016 and November 30, 2016, or the greater of the prime rate, the federal funds rate plus 0.50% or the daily rate equal to one-month LIBOR plus 1.75%, in each case plus a spread of between 0.00% and 1.00% based on a pricing grid tied to the Company's leverage ratio. In addition, commitment fees are payable on the unused portion of the credit facilities at rates between 0.20% and 0.40% based on a pricing grid tied to the Company’s leverage ratio.

The Amended Credit Agreement contains certain customary covenants, including covenants that limit the ability of the Company and its subsidiaries to enter into certain types of transactions. Financial covenants include covenants requiring maintenance of a minimum fixed charge coverage ratio, a maximum leverage ratio and a minimum asset coverage ratio. The Company’s obligations under the Amended Credit Agreement are guaranteed by substantially all of its subsidiaries. The credit facilities and the related guarantees are secured by senior first priority liens on certain of the Company's and its subsidiaries’ assets, including equipment, inventory and accounts receivable.

The Company also had an unsecured, uncommitted $25 million credit line with Wells Fargo Bank, N.A. that expired on April 1, 2016. Interest rates were set by the bank at the time of borrowing. The Company had no borrowings outstanding under this credit line as of February 29, 2016 and August 31, 2015.